That followed successes against Wasps, 17-12, and Harlequins, 33-0, and Saracens ended up doing just enough to win on points difference.
And having not quite been able to find the winning score against Irish, Mordt admitted the pressure was on to rediscover that winning form at the Rec in three weeks' time.
He said: "I truly believe we had a win in us [against London Irish], we hadn't had the ball too much in that second half. By the end they were a little bit out on their feet and a little bit worse than us.
"Just to have held on to the ball we may have won it but it was not a bad result at all.
"The teams are very evenly matched so we are just very happy that we have gone through as the winners.
"It is a taste for the beginning of the season and the double header. It is a great occasion. It would be better if the weather was a little bit nicer but I think it is growing into something big.
"You can see the teams getting selected and the competition between the sides is growing every year."
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